include/asm/system.h

   1 #ifndef SYSTEM_H
   2 #define SYSTEM_H
   3
   4
   5 extern unsigned long long * idt;
   6 extern unsigned long long * gdt;
   7
   8 #define move_to_user_mode()                     \
   9   __asm__ ("movl %%esp,%%eax\n\t"               \
  10            "pushl $0x17\n\t"                    \
  11            "pushl %%eax\n\t"                    \
  12            "pushfl\n\t"                         \
  13            "pushl $0x0f\n\t"                    \
  14            "pushl $1f\n\t"                      \
  15            "iret\n"                             \
  16            "1:\tmovl $0x17,%%eax\n\t"           \
  17            "movw %%ax,%%ds\n\t"                 \
  18            "movw %%ax,%%es\n\t"                 \
  19            "movw %%ax,%%fs\n\t"                 \
  20            "movw %%ax,%%gs"                     \
  21            ::)
  22
  23
  24
  25
  26
  27 #define cli() __asm__("cli\n\t")
  28 #define sti() __asm__("sti\n\t")
  29 #define nop() __asm__ ("nop"::)
  30
  31 #define iret() __asm__ ("iret"::)
  32
  33
  34
  35
  36
  37 #define _set_gate(gate_addr,type,dpl,addr)                        \
  38   __asm__ ("movw %%dx, %%ax\n\t"                                  \
  39            "movw %0, %%dx\n\t"                                    \
  40            "movl %%eax, %1\n\t"                                   \
  41            "movl %%edx, %2"                                       \
  42            ::"i"((short)(0x8000 + (dpl << 13) + (type << 8))),    \
  43             "o"(*((char *)(gate_addr))),                          \
  44             "o"(*(4 + (char *)(gate_addr))),                      \
  45             "d"((char *)(addr)), "a"(0x00080000))
  46
  47 #define set_intr_gate(n,addr)                   \
  48   _set_gate(&idt[n],14,0,addr)
  49
  50 #define set_trap_gate(n,addr)                   \
  51   _set_gate(&idt[n],15,0,addr)
  52
  53 #define set_system_gate(n,addr)                 \
  54   _set_gate(&idt[n],15,3,addr)
  55
  56
  57 #define _set_tssldt_desc(n,addr,type)                                   \
  58   __asm__ ("movw $104,%1\n\t"                                           \
  59            "movw %%ax,%2\n\t"                                           \
  60            "rorl $16,%%eax\n\t"                                         \
  61            "movb %%al,%3\n\t"                                           \
  62            "movb $" type ",%4\n\t"                                      \
  63            "movb $0x00,%5\n\t"                                          \
  64            "movb %%ah,%6\n\t"                                           \
  65            "rorl $16,%%eax"                                             \
  66            ::"a" (addr), "m" (*(n)), "m" (*(n+2)), "m" (*(n+4)),        \
  67             "m" (*(n+5)), "m" (*(n+6)), "m" (*(n+7))                    \
  68            )
  69
  70 #define set_tss_desc(n,addr) _set_tssldt_desc(((unsigned char *) (n)),((int)(addr)),"0x89")
  71 #define set_ldt_desc(n,addr) _set_tssldt_desc(((unsigned char *) (n)),((int)(addr)),"0x82")
  72
  73
  74
  75 #endif  /* system.h */